Photometry and Spectroscopy of the System V4641 Sagittarii in Quiescence

Details Photometry and Spectroscopy of the System V4641 Sagittarii in Quiescence Photometry and Spectroscopy of the System V4641 Sagittarii in Quiescence

Sep 2003

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003arep...47..740g&link_type=abstract

Astronomy Reports, vol. 47, Issue 9, p.740-749

Astronomy and Astrophysics

Astronomy

3

Scientific paper

We present the results of our CCD photometric and moderate-dispersion spectroscopic observations of the binary system V4641 Sgr, which contains a black hole of mass ≈9.5M &sun; and a normal B9III star. The photometric light curve reveals an ellipticity effect with very high amplitudes in V and R, 0.40m and 0.37m, and the color curve shows that the surface temperature is nonuniform. All this testifies to tidal distortion of the normal star's surface due to the massive companion and to a high inclination of the orbit to the line of sight. In June and July 2002, during quiescence, we obtained data during three flares with amplitudes up to 0.26m. In particular, spectroscopic observations were acquired near the time of the black hole's inferior conjunction. One hour before conjunction, a depression by EW=0.5 Å was observed in the red wing of the Hα absorption line, interpreted as absorption by gas flowing in the direction from the observer toward the normal star. This flow is apparently associated with a rarefied gas disk around the black hole, and the conjunction grazes the stellar surface if the orbital inclination is close to 70.7°. The maximum velocity along a circular Keplerian orbit is 650 km/s at a distance of R=0.15 0.20a from the black hole (where a is the component separation). Thus, we find the mass of the black hole to be M BH =7.1 9.5M &sun;, confirming the model of Orosz et al. (2001).

Affiliated with

Also associated with

No associations

Rating

Photometry and Spectroscopy of the System V4641 Sagittarii in Quiescence does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Photometry and Spectroscopy of the System V4641 Sagittarii in Quiescence, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photometry and Spectroscopy of the System V4641 Sagittarii in Quiescence will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1151497